Background Although preterm birth less than 37 weeks gestation is the leading cause of neonatal morbidity and mortality in the United States, the majority of data regarding preterm neonatal outcomes come from older studies, and many reports have been limited to only very preterm neonates. Delineation of neonatal outcomes by delivery gestational age is needed to further clarify the continuum of mortality and morbidity frequencies among preterm neonates. Objective We sought to describe the contemporary frequencies of neonatal death, neonatal morbidities, and neonatal length of stay across the spectrum of preterm gestational ages. Study Design Secondary analysis of an obstetric cohort of 115,502 women and their neonates who were born in 25 hospitals nationwide, 2008–2011. All live born non-anomalous singleton preterm (23.0–36.9 weeks of gestation) neonates were included in this analysis. The frequency of neonatal death, major neonatal morbidity (intraventricular hemorrhage grade III/IV, seizures, hypoxic-ischemic encephalopathy, necrotizing enterocolitis stage II/III, bronchopulmonary dysplasia, persistent pulmonary hypertension), and minor neonatal morbidity (hypotension requiring treatment, intraventricular hemorrhage grade 1/2, necrotizing enterocolitis stage 1, respiratory distress syndrome, hyperbilirubinemia requiring treatment) were calculated by delivery gestational age; each neonate was classified once by the worst outcome they met criteria for. Results 8,334 deliveries met inclusion criteria. There were 119 neonatal deaths (1.4%). 657 (7.9%) neonates had major morbidity, 3,136 (37.6%) had minor morbidity, and 4,422 (53.1%) survived without any of the studied morbidities. Deaths declined rapidly with each advancing week of gestation. This decline in death was accompanied by an increase in major neonatal morbidity, which peaked at 54.8% at 25 weeks of gestation. As frequencies of death, and major neonatal morbidity fell, minor neonatal morbidity increased, peaking at 81.7% at 31 weeks of gestation. The frequency of all morbidities fell beyond 32 weeks. Neonatal length of hospital stay decreased significantly with each additional completed week of pregnancy; among babies delivered from 26 to 32 weeks of gestation, each additional week in utero reduced the subsequent length of neonatal hospitalization by a minimum of 8 days. The median post-menstrual age at discharge nadired at 35.7 weeks post-menstrual age for babies born at 32–33 weeks of gestation. Conclusions Our data show that there is a continuum of outcomes, with each additional week for gestation conferring survival benefit while reducing the length of initial hospitalization. These contemporary data can be useful for patient counseling regarding preterm outcomes.

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To determine the factors associated with an increased risk of developing varicella-zoster virus (VZV) pneumonia during pregnancy, a case-control analysis was done in which 18 pregnant women with VZV pneumonia were compared with 72 matched control subjects. VZV infection was identified clinically, and VZV pneumonia was diagnosed by dyspnea and findings on chest radiographs. Of 347 pregnant women with VZV infection, 18 (5.2%) had pneumonia treated with acyclovir, and none died. Mean gestational age at rash onset was 25.8 plus minus 8.8 weeks for patients with pneumonia and 17.7 +/- 10.3 weeks for control subjects, which was not significant in the multivariable model. Women with VZV pneumonia were significantly more likely to be current smokers (odds ratio [OR], 5.1; 95% confidence interval [CI], 1.6-16.7) and to have > or = 100 skin lesions (OR, 15.9; 95% CI, 1.9-130.2). Pregnant women with VZV infection may be more likely to develop varicella pneumonia if they are smokers or manifest > or = 100 skin lesions.

Objective To assess whether 17 alpha-hydroxyprogesterone caproate reduces the rate of preterm birth in women carrying triplets. Methods We performed this randomized, double blinded, placebo controlled trial in 14 centers. Healthy women with triplets were randomized to weekly intramuscular injections of either 250 mg of 17 alpha-hydroxyprogesterone caproate or matching placebo, starting at 16-20 weeks and ending at delivery or 35 weeks of gestation. The primary study outcome was delivery or fetal loss prior to 35 weeks. Results One hundred thirty-four women were randomized, 71 to 17 alpha-hydroxyprogesterone caproate and 63 to placebo; none were lost to followup. Baseline demographic data were similar in the two groups. The proportion of women experiencing the primary outcome (a composite of delivery or fetal loss prior to 35 0/7 weeks) was similar in the two treatment groups : 83% of pregnancies in the 17 alpha-hydroxyprogesterone caproate group and 84% in the placebo group, relative risk (RR) 1.0, 95% confidence interval (CI) 0.9 to1.1. The lack of benefit of 17 alpha-hydroxyprogesterone caproate was evident regardless of the conception method or whether a gestational age cut off for delivery was set at 32 or 28 weeks. Conclusion Treatment with 17 alpha-hydroxyprogesterone caproate did not reduce the rate of preterm birth in women with triplet gestation.